Dampener assembly on offset printing machine



Feb. 15, 1966 M. LEEMANN 3,234,372

DAMPENER ASSEMBLY 0N OFFSET PRINTING MACHINE Filed Sept. 25. 1963 l9 I6 20 I30 l2 IO ll United States Patent Ofitice 3,234,872 Patented Feb. 15, 1966 3,234,872 DAMPENER ASSEMBLY N OFFSET PRINTING MACHINE Mario Leemann, Alfred-Escher-Str. 5,

Zurich, Switzerland Filed Sept. 23, 1963, Ser. No. 310,540 Claims priority, application Austria, Sept. 24, 1962, A 7,554/ 62 1 Claim. (Cl. 101-147) The present invention relates to offset printing machines in general and in particular to improvements in the dampening attachments thereof. Such dampening assemblies or attachments comprise a storage roller and two moisture-transfer rolls in rolling contact with said roller.

In order to obtain a good dampening of the impression or printing cylinder, the damping agent is supplied to said cylinder through different rollers serving for the distribution thereof. Aside of the construction of these additional rollers, their accurate relative bearing arrangement is important, as any slight difference in the spacing of the bearing bushes or 'brasses has a great influence on the pressure of the rollers relatively to each other. The individual bearing arrangement thus requires maximum precision of execution and only yields satisfactory results with the aid of complicated constructions.

The primary aim of the bearing arrangement disclosed by the present invention is a good mutual bearing arrangement while using readily produceable elements, and the possibility of fine adjustment therefor.

The bearing arrangement of a dampening attachment for an offset printing machine is characterized, in accordance with the present invention, by two bearing blocks arranged respectively laterally of the rollers and each comprising a V-groove guide in which are mounted the roller journals.

The forms of the invention are shown the drawing, in which FIG. 1 is a sideview of the open bearing block of a dampening attachment of a first form comprising a storage roller, transfer roll and printing cylinder;

FIG. 2 is a sectional view of the open bearing block of a dampening attachment of a second form comprising a storage roller, transfer roll and printing cylinder and taken substantially along the line 2-2 of FIG. 3 in the direction of the arrows; and

FIG. 3 is a top plan View of the dampening-attachment bearingarrangement according to FIG. 2, the bearing 'block being closed.

The bearing block 1 comprises a V-shaped guide groove 2 in which are mounted the journals of the dampening-attac-hment rollers.

The dampening attachment according to FIG. 1 comprises a storage roller 3 and journal 3a thereof, two transfer rolls 4 and 4' Which are directly adapted as axles, and two dampening rollers 5 and 5 with their journals 5a and 5a which latter rollers abuts against cylinder 6. By means of a manually adjustable gear 8 which meshes with a rack portion 7 of bearing block 1, the storage roller 3 may be moved towards cylinder 6 and away from same, which arrangement yields a higher mutual engaging pressure of the rollers 3, 4, 4', 5 and 5' schematically in on one hand and of the two rollers 5, 5' against cylinder 6 on the other hand. In the embodiment just described, the open side of the V-shaped guide points towards cylinder 6.

The dampening assembly shown in FIGS. 2 and 3 comprises a storage roller 13 that is mounted on the journal 13a and abuts against cylinder 16. Journal 13a and the journals of the transfer rollers 14, 14 are mounted in the V-shaped guide groove 12 of bearing block 11. The latter again is radially movable with respect to cylinder 16. To prevent the journals of the rollers 13, 14 and 14' from leaving the groove when pressing said rollers against cylinder 16, a retaining pin 10 is provided. The vertex of the V-shaped guide groove points towards the cylinder 16. The dampening attachment is driven by cylinder 16, namely via friction disc 19 which is in frictional connection with a rubbing ring 20 that is secured to the storageroller journal 13a. In this form of invention also, block 11 is movable relatively to cylinder 16, and such adjustment is effected by means of a contacting screw 21.

The opening angle of the V-shaped guide grooves 2 and 12 is suitably less than in order to raise the contact pressure of the rollers and to prevent an excessive lateral pressure of the journals on the groove. In the first form of invention (FIG. 1) in particular, the vertex of the groove may be formed as bearing bush. To lower the fabrication costs of the blocks 1 and 11, the journals are mounted in ball or roller bearings which are disposed in the two guide grooves, 2, 12 arranged laterally of the dampening assembly.

The dampening agent suitably is supplied to the storage roller.

The dampening assemblies described run without special drive, since they are in direct rolling contact with cylinder 6 or 16. All of the three or, respectively, five rollers may be set with the aid of two adjusting means, ie by means of the two bearing blocks.

As the pressure acts from roller to rolle.r--in contradistinction to the conventional arrangement with pressure from roller bearing to roller hearing-21 uniform pressure is obtained on the printing cylinder and the roller journals cannot be bent.

The dampening attachment may be readily and easily mounted on any offset printing machine.

I claim:

In an offset printing machine having a dampening attachment for dampening a printing cylinder, the dampening attachment including a storage roller and two transfer rollers in rolling contact therewith, bearing means comprising a bearing block disposed at each end of the rollers, each of said blocks being formed with a V-shaped guide groove, journals located at the ends of the rollers and mounted in said guide grooves, means for moving said bearing blocks and rollers as a unit radially relative to the printing cylinder, a pair of dampening rollers, the vertex of each of said guide grooves pointing away from the printing cylinder, the ends of said guide grooves being open and directed towards the cylinder, the dampening rollers having end journals mounted in said guide grooves so that the dampening rollers are located in abutting relationship intermediate the cylinder and said transfer rollers, a journal of the storage roller being located in said V-shaped guide groove at the vertex thereof, and

3 4 said groove being rounded at said vertex to provide a 2,530,282 11/1950 Brodie et a1. 101350 bearing bush for the storage roller journal. 3,094,065 6/1963 Roberts 101148 R f C b h E 3,134,328 5/1964 Yelmgren 101350 478,254 6/1929 Germany. 4/1904 Scott 10135I X 2/1926 Nall 1 11 7 ROBERT E. PULFREY, Primary Examiner. 9/1932 Waterworth 27068 X 3/1935 Buttner 101 350 EUGENE R. CAPOZIO, Exammer. 8/1939 Jordhoy 1o1 35'2 HARLEIGH P. EWELL, Assistant Examiner. 

